Thermal interface material (TIM) is often used in electronics between components to increase thermal transfer efficiency between the components. TIM is also known as a gap pad since it can flexibly fill surface imperfections on the components. Such surface imperfections would otherwise hinder heat transfer between the components since air is a poor conductor of heat with a thermal conductivity of 0.024 W/mK.
Although TIMs can typically achieve a thermal conductivity of approximately 1 to 5 W/mK, this thermal conductivity is still much lower than the thermal conductivity for other less flexible, but thermally conductive materials such as aluminum.